In situ X-ray diffraction studies of aluminium-induced crystallization of hydrogenated amorphous silicon

摘要

Thin intrinsic hydrogenated amorphous silicon (alpha-Si: H) films (5000 Angstrom thickness) were deposited on (111)-oriented n-type silicon substrates by plasma-enhanced chemical vapor deposition. A 4000 Angstrom thick Al film was then deposited on the alpha-Si: H film by vacuum evaporation. In situ annealing of these films was carried out in an evacuated temperature-controlled ( Model TTK) camera of an X-ray diffractometer at a glancing angle of 5degrees using a thin-film optics attachment. The crystallization behavior of aluminium-capped alpha-Si: H was monitored using the 111 silicon peak as a function of annealing temperature between 273 - 523 K. The results show that aluminium-induced crystallization of alpha-Si: H initiates at a temperature between 413 and 423 K. The crystallization rate increases with increasing temperature, and saturates for an anneal of 30 min at a temperature of 523 K. [References: 16]